The Return Coming
by ProfessorCactustheThird
Summary: -Sequel to Home Coming, please read that first!- Tadashi's back home and settled down, and things can't seem to be going any better for the gang. But of course peace and calm are never the lives of superheros. When old enemies rise and some of their own fall, it is up to the team to get through this together. (Rated for language and battles later on)
1. Prelude

Whoop! Thank you everyone again for all you awesome responses to Home Coming, and here's the sequel I promised y'all! This chapter is kind of an extended preface to what I posted at the end of Home Coming, we'll start getting into the action from the next chapter :)

Hope I don't disappoint anyone with this...

* * *

**-One year after Home Coming-**

The team had gathered at the Lucky Cat Cafe for their almost ritual tea break after classes had ended for the day. Go Go, Honey, Fred and Wasabi were just entering their third year, and Tadashi, who had missed one semester anyway due to his coma, had decided he might as well miss another one and go parallel with his brother, now in his second year. Everything was going amazingly well, the cafe business was thriving as almost everybody wanted to come in and try to meet the superhero team, Tadashi had gone with Fred's idea of his power being a force field (probably one of the proudest achievements of the school mascot's life as the team had _finally _listened to one of his crazy ideas), and the team was actually getting credit in school for when they had to skip to perform their superhero duties (the school felt it was the least they could do for one of their ex-professors becoming a villain and almost killing all of them).

Go Go slapped Wasabi with her school binder, eliciting a yelp from the latter. The rest of the team burst out laughing as Wasabi was the victim of the day in their favorite way to call down Baymax, who was often left deactivated in the Hamada boys' bedroom during the school day.

Right on queue, they heard the sound of squeaking vinyl coming down the stairs toward them. "I heard a sound of distress, what seems to be the- were you trying to get me down without physically coming up to activate me?" The robot was learning quickly about the quirks of his favorite humans, much to Tadashi's pride and joy. Wasabi nodded, still rubbing his head- Go Go could hit _hard_\- but waving off Baymax's attempts at attending to him.

"You should always try to include physical exercise in your daily activities, in order to live a long and healthy life." The team put up with Baymax as the robot repeated his daily health advice to the team, though he knew that their exertion during missions more than made up for not climbing up the stairs to activate him.

On this day however, Hiro was uncharacteristically quiet, something that did not go unnoticed by anyone. Tadashi lightly elbowed him in the ribs, but instead of his usual outburst and trying to hit Tadashi back, Hiro just flinched and continued staring down at the wood grain of the table.

"What's wrong kiddo?" Tadashi ventured, now worried about his younger brother, but Hiro just shook his head and refused to look up.

"Your neurotransmitter levels indicate you are worried and stressed." Baymax informed, the last time he had seen his little patient this emotionally down was just after Tadashi's 'death'.

"I was researching for my latest assignment," Hiro voice was so small that even Tadashi and Wasabi who had been sitting on either side of him barely heard.

"Hmm?"

"I was researching for my latest assignment," he repeated a little louder. "You know the one where they proposed teleportation." His voice dropped again toward the end of the sentence.

The team looked up when they heard the word. The idea by Krei Tech that had pretty much single-handedly set in motion the wheels for everything that happened since the SFIT showcase.

"Oh Hiro," Honey sighed sympathetically, reaching across the table to squeeze Hiro's shoulder. "All the bad stuff is over kiddo. It's okay."

Hiro shook his head firmly. "No. It's not."

"Hiro..."

"Yeah it reminded me of the whole thing with Krei and the Silent Sparrow, so I just looked them up-"

"And by 'looked up' you mean you hacked their internal servers?" Tadashi smirked, knowing his brother too well, and also trying to lighten up his mood.

Hiro made no attempt to respond to his brother's snark, "- And I found they have fixed the damage Callaghan made to the portal. They're trying to open it again."

The original Big Hero 6 members gasped, dropping their forks and spitting out their drinks, but Tadashi didn't get the full implication of what Hiro had just revealed. "Isn't that good? You can get your microbots back right?"

Hiro sighed, looking at his brother. "It's not just the microbots, Dashi. The original Baymax is in there too."

"Hey that's even bett..." The older Hamada trailed off as the saw five solemn pairs of eyes look up at him.

"Dashi, that Baymax only has his fighting chip inside him. And he only knows one command: destroy."

* * *

**-Around the same time-**

"They're doing it again."

"_What?_"

"They're doing it again."

"Why?"

"I don't know _why_, but they are."

"Hmmm."

"What?"

"I'm sure you know."

"But didn't you already get what you wanted?"

"My main motive I achieved, yes. But they shouldn't be able to buy food for their children, let alone play with their precious... _toys _again."

"Isn't that taking it a bit too far?"

"_They _had no qualms about 'taking it a bit too far', why should I?"

"But..."

"Just find a way into the system, and find me a way out."

"Okay, if you say so."

"Oh, and one more thing: the other ones, their most precious... things are inside it as well. Make sure you get them, and make sure you get them on our side. The blueprints are in my lab."

The man watched as the slender brunette- his only link and ally- nodded and left the room. He didn't know how this was going to ultimately turn out, but so far he knew only one thing- she had better do what she was told and not mess anything up.

**-One Week Later-**

That same brunette walked into the excessively lavish offices, feeling her partner's anger toward its occupants and their comfortable lives slowly bubbling inside her as well. Why did they have to struggle to get through everyday while these... these _bastards _continue to enjoy life so blissfully ignorant of all the hurt that they had caused? She had initially been hesitant to hurt anyone, but the more the she walked through the seemingly never-ending halls lined with marble and covered almost floor to ceiling with the latest technology, she started wishing she could just, just rip everything here to the tiniest shreds, including everyone inside.

"Hello boys." She laughed as some of the richest and most influential men in the whole of San Fransokyo froze upon sight of her.

"Wha... what are you doing here?"

"Oh you know, just thinking of coming back. I heard you guys are starting it again, I want in."

"Are... are you sure? I mean-"

"_Yes _I am sure," she insisted, losing her patience steadily. "Just let me back in."

"Uhm okay then. Come with me, I'll take you down to the lab and re-introduce you to everything and all." Krei shot one last look at his colleagues before leading Abigail Callaghan to level UG-5, where they were re-starting Project Silent Sparrow.

* * *

Yeah, I know that was pretty predictable but I hope you guys would want to put up with this? Do tell me what you think but no flames please, I'm pretty sensitive to them after a bad experience once :/

I love all of you guys!


	2. Learning

**Hey guys! Gosh, I'm so so sorry for not updating this in forever. I was crazy busy plus I got a bit of writer's block, and that's never a good combination haha. But yeah, my bad, and I think I've got this story back on track (i.e. I know roughly where, when and what stuff will happen, but I haven't really gotten around to writing the fine details, so don't expect too frequent updates from me :/ ) I'm so sorry once again!**

**But a huge thank you for those you reviewed/favourited/followed, it was you guys that really gave me the kick I needed to get working on this story again :) I've answered some things you guys brought up in the end author's note, hope you guys are okay with the way I'm planning things!**

**Enjoy!**

* * *

_["Dashi, that Baymax only has his fighting chip inside him. And he only knows one command: destroy."]_

"Wait what?"

Hiro looked down shamefully, "You know the red chip Baymax with all his karate and fighting programming? The only reason he is still so kind and friendly is because his primary healthcare chip overrides most of the information. Without the healthcare chip…" The boy genius trailed off, still unable to forgive himself for what he had almost done that day on the island, not just to Callaghan but especially to his own team.

"My healthcare protocol becomes violated. I almost killed Callaghan, and hurt some of the team when Hiro threw out my primary chip to get me to attack Callaghan." Remorse was apparent even as the robot's voice remained monotonous.

"You _what_? Hiro!"

_Probably should have mentioned it to him sometime before. _"Look I'm _sorry_, okay? It's just that when Callaghan didn't even flinch about you running into the building to save him from the fire _he _had _set, _I-"

Tadashi sighed, not wanting to resurface those memories again. "Okay, but you said you deactivated him in the portal right?"

"Well yeah, but if they find a way to reactivate him somehow, and the only command he knows is destroy then... Oh my god what have I _done _Dashi? I created a monster too, I'm no better than Callagh-"

"NO." Tadashi shook his younger brother out of his panicked rant. "Hiro don't think like that. You are _nothing_ like Callaghan, you hear me?"

"I-"

"Do you know when they're going to reopen the portal?" Go Go jumped straight to the matter at hand, knowing that dwelling too much in emotions wouldn't get them anywhere.

"I… I think their first try is in about two weeks. I don't know if they're actually going to try and use it or just see if it's working again."

The other members of the team looked at each other, trying to let the information sink in. They had only _two weeks _before another potential disaster?

Go Go chewed on her gum, deep in thought. "Okay best case scenario, the original Baymax is deactivated so all we need to do is take out the fighting chip. Worst case… wait he doesn't have any armour right? Then what's the big deal guys, we just need to puncture it so it can't really move."

"OOH!" Fred jumped up, waving his hand, "I _totally _rocked at darts as a kid. I can take evil Baymax down any day. And I don't even need my suit."

"While I would have normally punched you in the face, I have to say that today, this numbskull might have a point. It seems pretty straightforward to take down original Baymax, no matter how intent on destruction he is."

Honey nodded thoughtfully, "Yeah, I mean how much damage can an unarmoured Baymax actually do, righ-"

She was interrupted by a huge crash, as Baymax had accidentally turned around, right into Aunt Cass, sending trays scattering all over the cafe.

"Oops."

"Tadashi! Hiro! How many times must I tell you to watch that robot of yours?"

"Sorry Aunt Cass," Tadashi smiled sheepishly, trying to help her pick up the trays, only to be shooed upstairs along with his brother, friends and robot.

The gang regrouped in the brothers' bedroom, much cleaner now that Tadashi forces Hiro to clean up at least once a week. (There was also the point about how Hiro was actually using Tadashi's side of the room again as extra storage space to reduce the clutter, but they hardly brought up those memories if they could help it.) Hiro plopped on his bean bag as usual, leaning against Tadashi who was carefully watching his robot to prevent any more mishaps.

"… So we were talking about how an unarmoured Baymax couldn't do any damage?" Wasabi glanced nervously at the gang.

"Well, it's still better than blowing your face off with his rocket fist."

"Yeah, but-"

'GYAHHHHH!" Fred's scream pierced the air, and the team turned to see him hopping around frantically, trying to shake off Megabot which was gripping his leg tightly.

"You are in distress."

"No kidding Baymax. Hiro save me!"

"On a scale of one to ten-"

"He'll be fine Baymax, no need to take care of him."

"Okay, I will override my healthcare commands for Fred."

"Wow thanks guys, I feel the love... URGH GET THIS THING OFF ME!"

Hiro sighed, trying to get up from his bean bag, only to be promptly pulled back down by Wasabi. "Let him suffer," the older boy whispered uncharacteristically, "He deserves this for messing up my workstation yesterday."

"I just don't want him to destroy my best fighting bot,"

"But you don't need a fighting bot if you're not going bot fighting."

"Do you want me to set it on you instead?" Hiro glared at Tadashi's smirk before releasing Fred from the death grip of Megabot that was now innocently flopping on the floor. As he bent down to pick up his prized robot, Hiro froze. The time when Tadashi had made him "think of a new angle" to invent something for the showcase flashed through his mind.

"My microbots,"

"Sorry kiddo?"

"My microbots. Krei always wanted my microbots, what if he gets them out of the portal and…"

'I don't know little buddy, he probably might not want to play around with the stuff that almost killed him and ruined his swanky new building."

"Says the guy who keeps trying to play with Megabot after it always almost kills him," Go Go scoffed, and Fred grasped his heart in and overdramatic mock hurt, but was interrupted by Hiro's computer before he could retort.

"Information system accessed."

The team turned to face the screens as Hiro scrambled to open the newest files he had hacked from Krei Tech, and Baymax's famous phrase summed up the team's reaction perfectly.

"Oh no."

The latest file was a name list of all the personnel involved in the reopening of the portal. And there, clear as day, under the list of main engineers who have complete access to the project, was the one that the team had hoped they would never have to see again: _Callaghan, Abigail_.

* * *

Abigail looked down at the twin portals from her position on the command centre. They had repaired the damage to the second original portal and had built another to the same specifications. The brunette had taken advantage of her complete security access to tweak the containment field specifications so as to ensure that the portals opened to the same hyperspace as the original two had.

She had initially been reluctant to mess around with the portals again, but after seeing the way Krei and his company pushed so hard to get what they wanted, she felt herself growing more and more into her cause, Of course, objectively speaking, Krei _had_ toned down his drive after all the events of two years ago, but Abigail herself was no longer the bright eyed, bushy tailed, eager young scientist she had been. Being arguably the single person most personally affected by Krei Tech's ruthless methods for 'scientific advancement', she wanted them to pay for their mistakes, just as she had had to.

"Back in the game, huh?" The brunette jumped as Krei spoke behind her, pulling her from her thoughts.

"Yea… yeah. Can't believe we're going to do this again."

"You sure you're okay with this? I really don't blame you if you don't feel up to this, I can arrange for you to work on one of our other projects."

"Trust me, I'm fine. Let's just hope it works properly this time, right?" She offered a sickly sweet smile at her boss, and turned to leave, rolling her eyes. It was physically exhausting and mentally draining to have to even maintain the shortest of polite conversations with anyone at Krei Tech, but the faster she got this stage over, the better.

_Time to prep the next stage._ A short drive in her unremarkable hatchback led her to San Fransokyo's largely abandoned warehouse district. She pulled into one of them, where she had laid out the important blueprints she had recovered from her father's study. They didn't have the ability to build their own machines and robots, what with him being in jail and all, so they decided to do what he had done the last time around.

"_That kid's microbots are surprisingly good at destroying stuff, make sure you use them. And if you can get that big robot working again, it will be helpful to have on our side too."_

Abigail was grateful that her father had made it a rule that students share their blueprints with him; they simply couldn't afford the time for her to figure it out by herself. She did feel the occasional pang of remorse for the city's latest superhero team- they had been through enough, she honestly felt- but she knew this wasn't about them. This was about that bastard Krei, and how he and his influential buddies were able to do anything and have a get out of jail free card, while her father was serving two consecutive life sentences (okay so maybe he deserved the first one on terrorism, but it wasn't his fault one of his students was stupid enough to run into the fire- he had made explicit care to ensure nobody else would be trapped in the blaze). Heck, the military had even covered part of the cost of rebuilding the new headquarters her father had managed to significantly damage.

Having painstakingly poured over every video and news article regarding her father's first spree on Krei, Abigail realised she would have to make certain small tweaks to the original plan. New ideas in mind, she settled in for the second to last weekend of intense engineering before it all went down.

* * *

**Yup, I know it's super short, but this is still the build up to the actual story, (hopefully) the chapters will start getting longer as we move along hehe**

**As I said above, some quick responses to the reviews I got:**

**-For those of you who asked about how the original evil!Baymax was going to be used despite being deactivated in the portal for so long, well, let's just say Abigail's got some tricks up her sleeve…**

**-As for Tadashi's power being a force field instead of an offensive weapon (fire or something), firstly I felt a bit bad for Fred to have Tadashi get a cooler fire power and steal his thunder hahaha but more importantly, Tadashi always comes across as a protective figure to me, so it seemed only fair that he would be the one to have the best defensive tech so he can save his team if and when he needs to :)**

**Hope you guys understand, and please keep on reviewing, it really makes my day ^^**

**Much love xoxo**


	3. Preparing

Oh my gosh, I'm so sorry for not updating sooner! I'm starting college next month and things have been really hectic :/

I'll try and update more frequently, but in the meantime hope you guys enjoy this next chap!

* * *

[_And there, clear as day, under the list of main engineers who have complete access to the project, was the one that the team had hoped they would never have to see again_: Callaghan, Abigail.]

The team was silent for a while, letting the entire implication of the information they had just accessed sink in. Why on earth would Abigail be back on the Silent Sparrow team, and to be so involved as to have full access to the entire project? That thing almost killed her, and set in motion all the events that lead to her father terrorizing the city and now serving two life sentences. Wouldn't a normal person want to get as far away from something like that as possible?

But for all that the six brilliant minds had running through their heads, the best anyone could verbally produce was Wasabi's weak "Wha-?"

"Look, maybe she wants to go back to ensure that nothing like what happened to her ever happens again," Tadashi offered after some time. After all, given how he had gone to see Callaghan in jail after all that had happened to him, he figured that he understood her frame of mind.

Baymax agreed with him, "Some people cope best with personal tragedy by going back to the scene of the trauma to receive closure, and possibly the satisfaction of overcoming the obstacles they had faced."

The rest of the team nodded, all of them slowly accepting the explanations offered to them. It did kind of make sense that Abigail would want to go back and see what they were doing now, on the project that had cost her so much. All of them, that is, except Honey Lemon.

"I don't know guys," she subconsciously twirled her hair as her eyebrows furrowed deep in thought. "Something about this seems a bit fishy to me. I mean, if she just wanted to see what was going on, I'm sure Krei would have let her in as a visitor, or she could have taken a low level job. Why take on such a massive responsibility again so soon?"

"Maybe so that she has a say if they keep doing reckless things?" Wasabi _really _didn't want to think of the worst-case scenario.

Something in Honey told her better than to let the issue go. "Why not just report them for the first incident so they wouldn't even be able to think about it again?"

"Yeah, but Krei is backed up by the top secret military and God knows who else, I don't think talking to your friendly neighborhood cop would get her anywhere," Go Go wondered out loud.

Hiro frowned lightly and began typing something again, this time pulling up Callaghan's prison visitor records after a few minutes.

"Okay, you really need to stop hacking government datab-" Tadashi's warning to his brother was cut short as the page began to load. Apart from Tadashi's visit last year, there was only one other name on the list. Granted she was his daughter and she probably wanted to see her father, but the visits were increasingly becoming too long too frequently to be purely innocent.

He might be its youngest member by far, but Hiro was also his team's leader, and he turned to face all of them. "I hate to say it guys, but I think we might possibly have to go through Callaghan 2.0, literally." He sighed, running a hand though his messy hair before he continued. "We need to buck up our skills again."

* * *

While the team was safely in the Hamada household learning about the possibility of a repeat Callaghan incident, Abigail found herself in the warehouse just beside the one her father had used to manufacture and store his microbots- until Hiro and Baymax had stumbled their way in, of course. The police had shut down said original warehouse upon Callaghan's arrest to search for more evidence. _And besides_, Abigail thought, _using the exact same warehouse is a little too predictable and unimaginative._

She lay out the blueprints of Hiro's microbots in front of her, as well as that of the Baymax Tadashi had made. Her father had given her clear instructions to use the microbots as he had- to destroy as much as she could. He didn't really have a problem with her hurting Krei and some of the other top guns, but she just could not bring herself to do so, no matter how much she and her family had suffered because of them.

Such a blatant disregard for human life, as bad as those people were and how much they had it coming, would make her no better than the worst of them. Abigail just wanted to be a whistleblower. Yes, she had a far more elaborated and high-tech plan than most others who just brought the incriminating evidence to media companies, but said others probably weren't stuck in hyperspace for months thanks to the recklessness of their bosses. Plus, she had no intention of being a murderer. That was not part of the plan.

She didn't have the blueprints for the armor Big Hero 6 had made for Baymax, but Abigail knew she would be able to quickly create a basic one, albeit without any weapons unfortunately, that should be able to hold off any opponents until she could complete her task. Being on the Silent Sparrow team both times, she had gained valuable knowledge- and materials- on how to make protective armor. Gathering all the materials she had sourced from her father's lab and Krei Tech itself, _thanks for giving me access to build your company's demise Krei, _she set to work, determined to finish making the neurotransmitter band, and a new armor and chip for Baymax by the end of the night.

Re-building the neurotransmitter mask based on the specifics Hiro had faithfully jotted down in the blueprints was no issue. Abigail was genuinely impressed that a kid almost 15 years younger than her could have come up with something like this all on his own, and in a matter of just a few weeks. She did feel a bit bad that said brilliant kid would have to go through something as horrible as this all over again, but she knew he was just collateral, something that might have to be sacrificed in the crossfire. She knew what she had to do, and she knew she would do it.

Sure enough, Abigail managed to build the neurotransmitter and Baymax's armor in a matter of a few hours, and write a new chip for the robot that would ensure it recognizes her and only her as the person it would take commands from. As the clock crept just past eight, she grabbed the band and the chip and got into her hatchback, headed straight for Krei Tech Industries where she knew the portal holding area would be empty by then.

_Time to get my bots._

* * *

The team was thankful that the semester had only just begun and that there was hardly any homework or projects to do as they drove over to Fred's mansion, a.k.a. their training base. As much as they hated to admit it, months of fighting petty criminals armed with little more than a few hand guns had toned down their ability to take on evil super villains and after all, Tadashi had never had to go into full combat yet so he needed to be taught the ropes.

With Heathcliff's help as a stand-in villain again, the team ran through their criminal apprehension skills, this time both individually and in various sub-teams. ("We might have to split up and attack from various angles," Go Go had noted. "It's best to try out in pairs or trios."). Needless to say, Tadashi, Hiro and Baymax were automatically cast as one sub-team, especially with Baymax being the only one between the three of them with any offensive weapons.

"You need to go on a test flight," Hiro commented to his brother as they observed the other four trying out various pairings and attack methods. "You haven't gone on a real combat flight, it gets pretty rough."

"Combat flight?"

"Try holding on while Baymax does air karate to break off microbot chains. It's not exactly a joyride."

"Would I really have to be flying though?"

Hiro glanced up at his brother (_I _really _need to hit my growth spurt soon_, he thought to himself), "Yeah, I mean you're the one with the defensive power, you need to be getting a bird's eye view of the whole thing so you'll know if anyone needs help."

Tadashi nodded, thinking over what Hiro had said while watching his friends sparring on Fred's expansive back lawn. Protecting the team, especially his little brother, _was _his top priority after all. "Let's go," he turned to head towards his robot, slipping his helmet on along the way.

Shouting across the lawn to let the rest know they were headed off, Hiro climbed on the Baymax, showing Tadashi how to carefully latch on to the second set of electromagnetic catches he had placed on Baymax's armor. "We'll do a few loops and drops and stuff, then head over to the old district so Baymax will practice his fighting without whining."

"I do not whine, I am a robot," Baymax might be encased in impressive and fearsome armor, but he was still the kind-hearted yet slightly confused robot inside. "But yes, I am hesitant to practice dangerous maneuvers above the main city."

"You're too innocent for your own good, buddy," Hiro shook his head, latching on to Baymax himself. "Let's show Tadashi what we really got. You know the drill- wings, thrusters, fly."

The robot obediently followed the commands, and soon Tadashi found himself hanging on for dear life as what he had meant to be a cumbersome healthcare robot performed death defying stunts off of anything he could find.

Hiro laughed at how scared his brother was. "Enjoy it, you big baby. You know Baymax won't let anything happen to us."

"Yeah but-" Tadashi bit back a scream as Baymax entered the railway tunnel, barely out flying a high-speed train, knowing Hiro would never let him live it down if he did.

"Just relax," Hiro sighed, unlatching his hands from Baymax's back and raising them up, reveling in the freedom flying gave him.

"No Hiro don't-" Tadashi unlatched his own hands to hold on to his brother, only to realize just how _exhilarating _this whole flying thing was. "Wow," he breathed as Hiro smiled, remembering the feeling of flying for the first time.

"Okay buddy," the younger brother leaned down toward the robot, "let's head over to the old area and show Dashi what real showboating is, shall we?"

"Fine, I'll admit it." It was simply impossible to deny how fun unrestricted flying was, even for Tadashi. "This is pretty cool."

Hiro perked up, ecstatic that Tadashi was _finally _agreeing with his stance on flying. "I _told_ you. What took you so long big br- woah Baymax! What's wrong with you?" Both brothers nearly slammed face first into Baymax's back plate as the robot uncharacteristically halted mid flight without any warning.

"I am sorry for the unexpected stopping Hiro, but my scans revealed the presence of Abigail Callaghan, over there." The robot pointed to an old warehouse just beside the one Yokai had decided to set up shop in.

"You have _got_ to be kidding me," Hiro muttered as he ordered Baymax to find them a quiet entry point. "Hope you're ready Dashi, looks like your first stealth mission is coming up a heck of a lot sooner than expected."

* * *

There we go!

I don't have a beta, so I apologize for any mistake in spelling/grammar/vocab etc.

Please to let me know what you think!

I love all you amazing people!


	4. Testing

_Whoops so much for a frequent update I'm so sorry! Starting college in a few weeks does that to you haha sighss_

_anyway, here's the next chapter! :)_

* * *

_["Hope you're ready Dashi, looks like your first stealth mission is coming up a heck of a lot sooner than expected."]_

Baymax landed quietly on the roof, above an air vent just big enough for the two brothers to sneak in. Hiro knew it would be too risky and time consuming for them to unarm Baymax and take him in with them, and besides, they needed a quick escape plan.

"So just keep quiet, don't trip over anything, don't let her know we're here."

"Oh really?" Tadashi shot back sarcastically. Hiro may have more experience than him creeping around a super villain's hideouts but he wasn't an _idiot_. "I thought we were going to barge in the front door and throw her a party."

Scowling at his brother, Hiro slipped through the vent, Tadashi following close behind, and Baymax scanning the warehouse from the roof, radioing in their position relative to Abigail's. Carefully balancing along an overhead platform (Hiro was glad the warehouses were built identical to each other so he had a rough idea of the layout), the brothers reached the area directly above where Abigail was pouring over the blueprints that _they_ had come up with, for the neurotransmitter band and Baymax respectively, machines whirring somewhere just out of sight.

Hiro looked away, unable to wrap his head around the fact that his tech was being used for evil, not again_. Why was I so _stupid _to build those things? _Ever the caring older brother, Tadashi squeezed his shoulder reassuringly, slowly guiding him out of the warehouse and back on to Baymax who dutifully took them back to Fred's as fast as possible, his scans of his youngest patient telling him better than to do tricks or stunts.

When the trio touched down on Fred's lawn, the rest were sprawled out on the patio, enjoying the snacks Heathcliff had brought out for them and blissfully ignorant of the danger brewing just a few miles away.

"Welcome back guys! How was the flight?" Fred greeted them enthusiastically, not noticing the brothers' somber attitudes. Hiro brushed past him, sliding down and sitting against the railing as Tadashi filled the team in on the latest developments.

The team visibly reeled back, the thought of having to go through the whole process again numbing them. Honey glanced back at the team's leader, who was now staring blankly at the grain of the wooden flooring. "Oh kiddo, you know it's not your fault right?"

"Yeah." Hiro stood up abruptly, almost knocking over Honey who kneeling beside him. He grabbed Baymax, and climbed back on to the robot.

"Hiro!" Tadashi just managed to grab onto Hiro's arm as the latter was latching on to Baymax again. "What are you doing?"

Hiro's tinted visor hid his emotions as he yanked his arm out of his brother's grasp, commanding the robot to fly, and leaving the rest of the team in the dust.

Tadashi stared after Baymax's smoke trail before slamming his helmet on the ground, "What the _hell_ is that idiot thinking?"

"He turned his and Baymax's radio off," Wasabi informed them nervously a few moments later, scared of what Hiro could do when he was so clearly unstable.

Go Go chewed on her gum, "He's probably headed to the warehouse right? We need to go stop him before he does something he'll regret."

"Yeah, but he kinda took our main mode of transportation with him,"

"Fred?"

Fred looked at them regretfully, "I'm sorry guys, but the 'rents took the chopper yesterday."

"Great," Tadashi threw his arms up in defeat. "Now by the time we get there he'd probably have…" he couldn't bring himself to finish the line of thought.

"I'll go get him," Go Go volunteered. "I am the fastest out of us anyway."

Tadashi nodded gratefully at her. She was the best person to slap some sense into Hiro as well. But Go Go barely had time to snap on her skates when Hiro and Baymax appeared back on the horizon, heading toward the house.

The landing was slightly rougher than usual, and Hiro jumped off his robot before Baymax could even fully touch the ground. Tadashi grabbed him tightly, ripping off his brother's helmet. "What were you _thinking_?"

"She's gone." Hiro informed them shortly. "I don't know how, or where, but she's gone. It's just perfect."

"Not again."

It didn't register to Hiro exactly who had said it, but it didn't matter. "If we can't beat her to it, we'll beat her _at_ it." He looked up at his team, "And we're going to need a better plan than the last time."

* * *

Abigail parked her car in the empty lot of Krei Tech, thankful that everyone left work early. Glancing at the neurotransmitter band in her hand, she felt her determination build up again.

It was time.

She found it almost hilarious how easily she managed to enter the underground lab that held the twin portals; even the toughest security measures in the world give way to those with the appropriate access cards. Abigail hoped the plan, and the neurotransmitter band, would work. _But if it doesn't the portals will ruin the building, so it works either way._

As Abigail fired up the portals, she felt her breath hitch as she looked into the abyss than had sucked her in for months, but she willed away those memories and focused at the task at hand. She gingerly slipped on the band, and almost teared up in joy as the microbots slowly began to slip out of the portal, piling up on the floor in front of her. Baymax was harder to retrieve, but after some careful tweaks to the containment field, and she was able to get rid of all the other debris, and saw the white robot floating within sight. She sent a stream of microbots to drag it out, relieved that it was still deactivated.

The scientist wasn't stupid, her father had told her how dangerous Baymax could be, and she wasn't sure exactly what would activate the robot, so she got the microbots to encase it just in case, and carry it back to her car for her, excited to get back to her warehouse and play around with her new toys.

* * *

The team headed back to Hiro and Tadashi's garage so they could build whatever they figured out would help them best.

"She couldn't possibly have the blueprints for Baymax's rocket fist and thrusters and stuff, right?" Honey asked.

"But he still has the chip, and that's more than enough."

Tadashi felt his heart break at his brother's tone, he knew the younger boy was blaming himself for everything. "Okay, but the fighting chip is only karate stuff? That means it would have to be in close contact with us to harm us."

"So if our Baymax can rocket fist him down from a distance and then we take out the chip…" Wasabi caught on to his friend's train of thought.

"Baymax fight!" Fred jumped up, before realizing it was slightly inappropriate given the general mood. "But yeah," he coughed, sitting back down awkwardly, "it shouldn't be a problem."

Hiro nodded, ignoring Fred's outburst. "Alright, that's one down. But the microbots…"

"Hiro, you _did _invent them after all, can't you build a band that could override the control of the original one, or at least shut them down or something?" To be quite honest, Tadashi didn't understand why they hadn't done that before.

"That's genius!"

"_Why_ didn't we think of that before?"

"Well I'm _sorry_ if I was a _bit_ upset the last time around." Hiro snapped uncharacteristically at this team, but went over to his computer and started pulling up the files for his microbots nonetheless.

_I'll talk to him_, Tadashi mouthed a promise to the rest as they followed Hiro, helping him build the new neurotransmitter the best they could without crossing any lines.

* * *

Abigail ordered the microbots to gently set Baymax down in the middle of the warehouse, opening its access port and removing the red chip before inserting her own and closing the port. Baymax activated at that, but without the healthcare chip its start up programming was wordless, and it simply stared at the woman before it.

"Hello Baymax," she smiled. "I'm Abigail, and you only take orders from me, understand?" The robot nodded blankly back at her, understanding but unable to verbally respond. Abigail didn't bother coming up for a new name for the robot, she had much more important things to do. And besides, she thought it would be fun to see the confusion that would ensue if Big Hero 6 decided her to engage her in a battle as they did with her father.

"Good, now what does this do?" She wondered to herself as she nervously replaced the red chip back into Baymax's access port. The robot's eyes turned red and she was scared for a moment, but then it spoke. "Fighting database downloaded." Its voice lacked the kind, caring tone Tadashi had programmed in the healthcare chip, now sounding cold, like any generic speaking computer. "How would you like to proceed?"

Abigail took a few steps back, not sure what 'fighting' entailed. "Show me what you have."

The robot systematically went through the karate moves stored in the chip, with Abigail getting more gleeful with each passing demonstration. "Perfect. Do you think you could use these actions against anyone who tries to oppose me?"

"If you are my commander, I will protect you."

"Good. Now try wearing this."

* * *

Later that night, much after the rest of the team had helped to finish up the new neurotransmitter band and left for home, Hiro woke up to Tadashi's computer whirring. The sound was muffled behind the divider between their halves of the room, but Tadashi's light was on as well so Hiro knew for sure his brother was up- Tadashi had to have pitch black darkness to even think of sleeping.

Pushing the covers off, Hiro crossed the room and opened the divider, "Dashi?"

"Hey Hiro," Tadashi turned and smiled at him. The older boy was secretly glad that Hiro had reverted to calling him by his childhood nickname for him after they found him in the hospital. Hiro had announced himself 'too mature for childish nicknames' when he was 11, and it had always been either 'Tadashi' or some version of 'bro' since. "You feeling better?'

Hiro sighed, sitting down on the foot of Tadashi's bed. "I was a jerk to you guys today, I'm so sorry."

"Nobody blames you, kiddo. They all get it, it's crazy to have to go through everything all over again."

"Yeah, but _they_ didn't snap."

"But they're not as personally involved as you are, kiddo. I mean it's not their tech that was stolen or anything."

Hiro nodded, remorse clear in his eyes despite the poor lighting Tadashi's table lamp offered. "I need to apologize to everyone though. I mean like you said, they have to go through everything again as well, they don't deserve to have me taking out my problems on them."

"Yeah, it'll be good if you talk to them in the morning, but trust me, they all understand." Tadashi was so proud of how much his little brother had grown over the past two years. Sure, it had taken unimaginable and heartbreaking tragedy, but the fact that Hiro had taken so much out of it was a true testament to his character.

"Why did I even do it?"

"You're stressed out, Hiro. It's norm-"

"No, as in the microbots. Why did I think it would be a good idea? Why didn't I build something more passive? Why… why couldn't I be more like you, Dashi?"

Tadashi's heart broke all over again for his baby brother, who was doubting his decision of creating one of the best inventions Tadashi had ever seen. "Oh Hiro," he stroked his back as he had done when they were younger, pulling him into a hug. "This was never the plan, and you know it kiddo. Remember when you were first making them? You had all these dreams to use them for transport, construction, all good and helpful things."

"I should have at least made safety catches, or personalized the neurotransmitter, or-" Hiro broke off, burying his head in Tadashi's shirt.

Running a hand through his brother's tangled mess of hair, Tadashi let Hiro cry out all the bottled up emotions he kept to himself, before pulling him up to lay down properly on his bed, knowing that the younger one would not get any sleep on his own tonight. Tadashi quietly finished up what he was working on and turned off the computer and light before settling down to sleep beside his brother.

Nobody knew when Abigail would strike, and if they needed one thing right now, it was enough rest to keep them sane and stable when the situation would eventually call for it.

* * *

_Thanks for reading! Please review, it really make me feel better about myself and my writing :))_

_I love you guys!_


End file.
